Abstract: Process of seal coating phosphoric acid anodized aluminum and aluminum alloys to improve the corrosion resistance and maintain the adhesive bonding properties. The process comprises post-treating phosphoric acid anodized aluminum and its alloys with an acidic aqueous solution comprising, per liter of acidic solution, from about 0.01 to 22 grams of a water soluble trivalent chromium compound, about 0.01 to 12 grams of an alkali metal hexafluorozirconate, about 0.0 to 12 grams of at least one alkali metal tetrafluorosilicate and/or an alkali metal hexafluoroborate, from about 0.001 to 10 grams of at least one water soluble divalent zinc compound and from 0.0 to 10 grams of a water soluble thickener and/or water soluble surfactant.

Abstract: Process of coating iron alloys to improve the corrosion resistance and adhesive bonding strengths. The process comprises treating the iron or iron alloys such as steel with an acidic aqueous solution comprising, per liter of solution, from about 0.01 to 22 grams of a water soluble trivalent chromium compound, about 0.01 to 12 grams of hexafluorozirconate, at least one tetrafluoroborate and/or hexafluorosilicate, at least one water soluble divalent zinc compound and from 0.0 to 10 grams of water soluble thickeners and/or water soluble surfactants.

Abstract: Pretreated aluminum and aluminum alloys and the process and composition for pretreating said aluminum and its alloys to provide a coating with color recognition for identification purposes and to improved the corrosion-resistance, electrical conductivity, and adhesion properties which comprises pretreating said aluminum and its alloys with an effective amount of an acidic aqueous solution having a pH ranging from about 2.5 to 5.5 comprising water soluble trivalent chromium compounds, alkali metal hexafluorozirconates, divalent zinc compounds, alkali metal fluoro-compounds, and effective amounts of water soluble thickeners, surfactants or wetting agents.

Abstract: Pretreated aluminum and aluminum alloys and the process and composition for pretreating said aluminum and its alloys to provide a coating with color recognition for identification purposes and to improved the corrosion-resistance, electrical conductivity, and adhesion properties which comprises pretreating said aluminum and its alloys with an effective amount of an acidic aqueous solution having a pH ranging from about 2.5 to 5.5 comprising water soluble trivalent chromium compounds, alkali metal hexafluorozirconates, divalent zinc compounds, alkali metal fluoro-compounds, and effective amounts of water soluble thickeners, surfactants or wetting agents.

Abstract: Aqueous compositions for post-treating metal coated substrates such as cadmium-plated steel, and zinc-nickel coated substrates and the process for using said compositions to provide a color recognizable coating and to improve the corrosion-resistance, abrasion, electrical, and adhesion properties of the coating. The post-treatment composition comprises an acidic aqueous solution having a pH ranging from about 2.5 to 5.5 and contains effective amounts of trivalent chromium compounds, alkali metal hexafluorozirconates, at least one divalent zinc compound, alkali metal fluoro-compounds, and effective amounts of water soluble thickeners, wetting agents or surfactants.

Abstract: An aqueous composition for post-treating metal coated substrates such as cadmium-plated steel or zinc-nickel coated substrates and the process for using said composition to improve the corrosion-resistance, abrasion, and adhesion bonding properties of the metal coatings. The composition comprising an acidic aqueous solution having a pH ranging from about 2.5 to 4.5 containing effective amounts of trivalent chromium salts, an alkali metal hexafluorozirconate, at least one alkali metal fluoro-compound, and effective amounts of water soluble thickeners and/or surfactants.

Abstract: Pretreated aluminum and aluminum alloys and the process for pretreating said aluminum substrates to improve its corrosion-resistance, and adhesion properties which comprises pretreating said aluminums with an effective amount of an acidic aqueous solution having a pH ranging from about 2.5 to 4.5 and comprises effective amounts of a trivalent chromium compound, alkali metal hexafluorozirconates, at least one alkali metal fluoro-compound, and small but effective amounts of water soluble thickeners and/or surfactants.

Abstract: Composition for post-treating anodized aluminum and aluminum alloys and the process for using said composition to improve the corrosion-resistance, abrasion, and adhesion bonding properties of the anodized aluminum and its alloys. The composition comprises an acidic aqueous solution having a pH ranging from about 2.5 to 4.5 containing effective amounts of trivalent chromium salts, alkali metal hexafluorozirconates, an alkali metal fluoro-compound e.g. fluoroborates and/or fluorosilicates, and effective amounts of water soluble thickeners and surfactants.

Abstract: Composition for post-treating anodized aluminum and aluminum alloys and the process for using said composition to improve the corrosion-resistance, abrasion, and adhesion bonding properties of the anodized aluminum and its alloys. The composition comprises an acidic aqueous solution having a pH ranging from about 2.5 to 4.5 containing effective amounts of trivalent chromium salts, alkali metal hexafluorozirconates, an alkali metal fluoro-compound e.g. fluoroborates and/or fluorosilicates, and effective amounts of water soluble thickeners and surfactants.

Abstract: An aqueous composition for post-treating metal coated substrates such as cadmium-plated steel or zinc-nickel coated substrates and the process for using said composition to improve the corrosion-resistance, abrasion, and adhesion bonding properties of the metal coatings. The composition comprising an acidic aqueous solution having a pH ranging from about 2.5 to 4.5 containing effective amounts of trivalent chromium salts, an alkali metal hexafluorozirconate, at least one alkali metal fluoro-compound, and effective amounts of water soluble thickeners and/or surfactants.

Abstract: This invention is for the protection and surface treatment of aluminum, aluminum alloys and coated aluminum substrates against corrosion. The aluminum substrates are treated with an acidic aqueous solution containing small but effective amounts of at least one trivalent chromium salt such as a trivalent chromium sulfate, at least one alkali metal hexafluorazirconate such as potassium hexafluorozirconate in combination with small but effective amounts of at least one water soluble or dispersible thickening agent such as a cellulose compound and at least one water soluble surfactant. The corrosion resistant aluminum substrates of this invention have improved adhesion for overlaying coatings e.g. paints and a lower electrical resistance contact.